Communication networks are known which include a plurality of nodes, which include an ingress node, one or more intermediate nodes, and an output node. Customer or client data is supplied to the ingress node, and then transferred from one intermediate node to the next until the data is output from the egress node. Conventional network management systems monitor and control the connections between nodes in order to select paths through the network over which the client data may be transmitted.
Conventional nodes in a network may be configured to “auto-discover” other nodes in a network, whereby a first node may transmit a signal, such as an optical signal, which carries identification information to a second node. Based on such identification information, the second node may determine or identify a connection with the first node, as well as the service provided by the first node (e.g., SONET, Ethernet, etc.). Such exchanges of information may occur throughout the network such that each node “knows” the connections and identity of every other node in the network. In addition, such information may be provided to a network management system, which may then use that information to determine a topography of the network, such that a data transmission path through the network can be obtained. Examples of known auto-discovery techniques are described in U.S. Pat. Nos. 6,718,141 and 6,968,131, the contents of which are incorporated herein by reference.
Although auto-discovery is effective in identifying connections in a network, additional components may be required to be provided at each node that transmit and receive node identification information. These additional components may add to the cost of each node, thereby increasing the overall cost of the network.
On the other hand, network nodes that do not provide auto-discovery, although less expensive than nodes that do, may be more difficult to monitor by the network management system. In addition, the network management system may have difficulty identifying a connection to and data path including such nodes.
Accordingly, there is a need to monitor nodes that do not provide auto-discovery and identify the connections to such nodes.